Network configuration is a complex and difficult task, often performed by skilled network administrators. This difficulty is compounded by each network differing from site to site and system to system.
Installation and configuration of an email gateway is a complex and difficult process. The specific configuration of an email gateway depends upon internal and external network configuration. Numerous factors impact proper functioning of an email gateway, including, the functioning of the network, the configuration of internal domain name servers (DNS or DNS server), the configuration of external DNS servers, the configuration and functioning of an internal mail transport agent (MTA), the configuration of firewalls, the network specific configuration such as network address translation (NAT), the state of the email gateway, and DNS verification failures.
Because networks are configured differently, there are many reasons why an email gateway may not be working properly. Any improper setting for an email gateway will likely impede full functionality of email communications. For example, if mail is not being received by the email gateway, it could be because the firewall is configured incorrectly, the mail exchange (MX) records of the DNS server are not pointing to the email gateway, or the email gateway is rejecting email because of DNS verification failures.
Presently for any problem that occurs with an email gateway, a user performs manual troubleshooting to determine the reason for the problem. Manual troubleshooting of email gateway functionality is a difficult and time consuming task that requires skill and knowledge of the email gateway, the network, and interoperability of the email gateway with the network and many individual network systems including DNS servers and firewalls. Manual troubleshooting of email gateway functionality is very network specific and usually must be done by hand from the system command line. Determining the exact reason why the email gateway is not functioning properly is the goal of troubleshooting and a difficult result to achieve. There are many unknowns and many settings to check. An improper setting may disable the entire email gateway, preventing a user from identifying the proper cause of the problem and distinguishing that cause from all other functioning network systems and properly configured settings. It is easy to miss checking a setting, make a mistake, or make an improper diagnosis during manual troubleshooting of the functionality of an email gateway.